5vz cracked head. reman heads or junk yard engine?

(made the same post in general Tacoma talk but meant to put it in here)

I have recently been on the hunt for the cause of excessive exhaust smoke, as well as subtle misfires upon cold starts. my 5vzfe has 325k miles, I recently did plugs, wires, coolant system flush, radiator cap, pcv valve. truck runs amazing, but the slightly sweet exhaust, extra smoke and the very inconsistent misfires has set me to dive deeper. I got the truck in winter, and have yet to see it run in warmer weathers so initially didn't think much of the extra smoke until its been warmer out.

I have gotten no CEL but misfires are noticable for about 10 seconds or so upon half (rough estimate) of cold morning starts in the past 2 weeks or so. The truck doesn't seem to want to do it all day after the first start regardless of how long it sits, only overnight in the morning starts.

The exhaust once driving and fully warm looks normal. here is a video of me blipping the throttle. The engine had been running for 5 minutes or so, Not thermostat open warm, but no longer cold. I did park the truck in the garage to see if it was condensation but clearly shes still huffing and puffing as shown https://youtube.com/shorts/_HK1zxFugNk?si=Rfy90H3yrWOYafpJ

When it comes to head gaskets and/or a cracked head, I have no symptoms other than what's stated. No milky oil or cap, no major coolant loss if any at all. I performed a block test with the weird liquid that changes color. after trying it for 5 minutes while the engine was warm, and this morning with the engine cold I no color change meaning i "passed" the test. The engine hasn't been overheated, temperatures sit at 187. (the smell of the exhaust doesn't smell like fuel, but it isn't obviously coolant. it is sweet, but me and a few others have just said it smells like old 90s truck.

Im really confused at this point. Im now thinking it could be something with fuel sys or intake. if anyone can come up with anything else, please let me know. I really hope I'm not chasing my tail around in circles with this one.

 

Might be a cracked head, between the valves and spark plugs. Serviced a Tacoma a few years ago that will show little to mild smoke during cold start and nothing once the engine heats up. This was during the summer, shouldn’t be smoking. What confused me at first was it held compression and passed. Passed the leak down test too, shows no exhaust gas in the cooling system. Decided to remove the heat to get the heads pressure test and cleaned. Before cleaning, nothing was noticeable.

Reman head installed, fixed the issue.

 

Couple of things come to mind, the first is ASAP and when it is safe, take the pressure off of the cooling system and let her sit overnight and see if it changes the next is to pressureize the system with a cooling system pressure tester and see if the pressure drops and/or keep pressure on the system over night and see what happens in the morning.

The issue as I see it is the mileage, who knows what you are going to find once you open her up, corroded heads, cracks or just a failed head gasket... cmon toyota, cant you make a truck that will last more than 30 years!

 

Ok so I'm planning to get a borescope down in there to see if I can notice any cracks in the heads. From what I can find though, through research, I'd be shocked if it wasn't a cracked cylinder head. anyway I get off school for the summer in a few weeks and obviously want to do an overhaul on my engine, or replace it completely/remanufactured heads while I have the time. I'm wondering what anyone else would do with a block that has 300k miles. is it even worth over a new engine or just buying a junk yard engine with low miles?
Im excited that I have opportunity and a reason to rip a motor apart, learn, etc. As a junior in high school, I dont make a bunch of money and spent most of it buying the truck. I did compression tests and looked over everything when i bought it so that i knew i would not have to do any major overhauls... oh well, ya live and ya learn.

 

Geez, you're a teenager? You're a smart dude to have figured it all out this far.

 

I appreciate the kind words. Yup, class of 2026! Lol. I got lucky with good taste. I don't really know where I grew a love for these early Toyotas but I'm sure glad I did. When I went to pick up a pcv valve about a week or so ago, I called the dealer right before 4 o clock to see if they could have it ready for me when I got there as they were closing at 4. Told them it was for my 95, and he goes "this sounds like a funny question but 4wd or 2wd model" haha. anyway I get there and the first thing he tells me that its normally old dudes getting parts for their early 90s Toyotas, never any younger adults. This did make me laugh but like I said, I love these trucks. I love anything that's OEM and original, taken care of. Im definitely not into the "living 3 feet closer to heaven with this lift kit" on wides lifestyle.

 

Old guy here, this is my 96 in Cabo San Lucas just after paint last year, as small trucks go, this is the best I have ever owned, she looks like yours. Funny how they have the same pose... runway models I guess.

 

So I went through this last year, 290k and started smoking on cold starts, sweet exhaust smell, and eventually found a crack in the heads with a borescope. Passed the exhaust gases in coolant test like nothing was wrong too..

See thread here:https://www.tacomaworld.com/threads/compression-test-white-smoke-cracked-head.824933/

I went with reman heads, and a refresh of a bunch of maintenance parts in the process.
Here is my conclusion post on that journey, and what I spent

TLDR: I spent like $3k, and my block still has nearly 300k miles on it. Could be done for ~$2k if you don't replace anything else while you've got it torn apart except gaskets and heads, but thats still a lot. If I were to do it again, I'd probably just go with a junkyard motor, or even dive into a 1 or 2uz swap.

If you go the reman head route, I'd do it asap to keep the block healthy. If you go with a engine swap, you could ride out this engine for a while (the smoke is embarrassing though). I got a friend with a 5vz 4runner whos had a cracked head for a few years now, its getting worse and worse but still driveable. Power loss has started getting pretty bad these days, smoke isn't as bad as yours though. Hes going to throw in a v8 when he finds a good deal or the thing finally blows.

 

I love it. Hoping to go over and re paint my hood/clean up some other small dings and such

 

i actually did read through this thread. I got some valuable information from it. Just to clarify your motor is running strong to this day? I guess what I will probably end up doing is finding a low mileage motor, find a set a heads for mine, rebuild it and keep it as a spare. when I'm looking for a motor, how can I know I'm buying a motor that's worth my money and time? never done any of this before. I don't really know what to look or check for. should i only buy one that I've seen run with my own eyes?

 

Runs great today, haven't had any engine issues since.
I haven't bought a motor before, and being worried about it being 'good' was definitely a component that made me lean towards just getting the new heads. If at all possible I would want to see it running. At the end of the day, it is at least a little bit of a gamble.

 

Highly doubt you'll find it with a borescope. When I removed the heads, there was no indication until the heads were cleaned and pressure test.

 

its worth a shot, especially in my situation. I cant really rip the heads off until I get time away from school. also James did find his with a borescope so I guess it depends.

 

This whole situation is a tough bullet to swallow... Il try my best to source some heads from somewhere. regardless if I get a different motor or not this block needs heads so.

 

Mine actually showed up way better on the borescope than once the heads were off
Probably depends a lot on the scope, carbon deposits on the head and getting light angle right to catch the crack

Yeah definitely not a fun thing to deal with. You probably saw this already from my thread but I'll throw it in here too, heres the comparison sheet I made for all the engine/head options I found when I was searching. Prices and lead times probably are no longer perfectly accurate, but should be in the ballpark. Junkyard option not included.

 

i found a guy locally that has a 115k mile 3.4 out of a 4runner for 2300 bucks. That seems like a steep price, but what would be a reasonable offer? i wouldnt buy it unless i tested it and/or heard it run. the guy has good reviews on fb and seems like he has a collection of these toyota parts.

 

Call me cynical, with all these pretty much 25 year old motors if it's not in the vehicle and you show me the odometer I don't believe 99% of the " it's only got a 120k driven by a little old lady in Pasadena on the weekends" salvage yards selling motors. I looked for 2 years before I bought a JDM engine focusing on a used engine from the likes of lkq, carparts.com, local yards, yards in adjacent cities and cities hundreds of miles away. Crooks and liars all trash and junk.

 

You have more sense than most teenage gear heads it would seem! It feels like every year there's at least one local news report about some highschool knuckleheads involved in a fatal brodozer rollover.

 

Buy a complete engine whether JDM or out of a running vehicle. IMO best and cheapest options. You can see a crack in my avatar.

 

I'll chime in with a vote for taking a gamble on a used engine. My buddy's '98 Tacoma (V6, 5spd, TRD) blew a head gasket last October. He got lucky and the only local pick and pull yard in pur area, had an '04 V6 Prerunner (AT) that had just arrived at the yard a few days prior. I went and pulled the motor (because I had Columbus Day off and he had to work), and he and I swapped it in over the next week.

The donor vehicle had a Carfax entry from only a month prior where the registration had been renewed at 171k miles. It also had a local community college parking pass with "2024" on it. The donor truck appeared to have been in a roll over accident, but the motor appeared fine and the interior of the truck was really nice. These motor also turned over by hand (with a ratchet on the crank bolt) nice and smooth, but also clearly built compression with the plugs in.

These signs all hinted that the truck had run (right up until the rollover) and had likely been well cared for prior. So he took a $400 gamble and that motor runs like a top. Fired up first crank after we swapped it in.